.header {
  display: flex;
  align-items: center;
}
h2 {
  margin-right: 10px;
}
.tab {
  display: flex;
}
.common.active {
  font-weight: bold;
  background-color: yellowgreen;
}
.common {
  text-align: center;
  width: 50px;
  margin: 0 5px;
  background-color: rgba(0, 0, 0, .5);
}